The present invention relates to the field of sign making and is concerned more particularly with the method of making multi-colored signs with a sign making machine.
U.S. Pat. Nos. 3,465,627 and 3,826,167 disclose sign-forming apparatuses which employ dies to cut through a thermoplastic sign material adhesively secured to a paper release material. The apparatus is designed to cut a series of sign characters such as letters or numbers, with appropriate spacing between the characters in accordance with the final positioning of the characters in a sign. The cut characters are then transferred from the release material to a signboard or other display object.
The sign material which is commercially available and used in the die-cutting machines described above is generally a flexible thermoplastic sheet such as a vinyl plastic film having a thickness of 3 to 4 mils with excellent heat, solvent and abrasion resistance. The thermoplastic sheet or film is available in a number of colors, and one brand is sold under the trademark SCOTCHCAL by 3M Corporation of Minneapolis, Minn.
A microprocessor-controlled sign-making machine may also be utilized for cutting characters, logos and other designs in a single ply of the sign material. Such a machine includes keyboards for entry of sign data and control of the machine functions. The characters are cut by means of one of several tools, including a heated stylus or a knife blade, and relative movement of the tool and material to cut the characters is controlled by preprogrammed vector commands that are stored for each character in a font memory such as a PROM. Various fonts of characters may be stored in the microprocessor or can be read from an external memory to generate selected characters.
It is an object of the present invention to disclose a method utilizing a sign making machine as described above or a manual method to cut characters and the like from sign material and make signs in multiple colors. It is a further object of the invention to provide a layup of sign material from which multi-colored signs can be generated in a single cutting operation.